Method of assembling blower wheels or the like



06L 1964 v. H. WILLIAMS 3,153,842

METHOD OF ASSEMBLING BLOWER WHEELS OR THE LIKE Filed April 17, 1961 2 Sheets-Sheet 1 lZ E I 25 49 lugn I. I f -5.

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BY T1061; Budd Hawk Oct. 27, 1964 v. H. WILLIAMS METHOD OF ASSEMBLING BLOWER WHEELS OR THE LIKE Filed April 17, 1961 2 Sheets-Sheet 2 O 4 IM-1 "9- W "film 0 a 3 Q Wi 5 R .M v. MM M T L E ma m W i b N United States Patent lice 3,153,842 METHQD 0F ASSEMBLING BLGWER WHEELS OR THE LIKE Vernon H. Williams, Columb ne, Ind, assignor to Verneo Corpnration, Celumbus, 11211., a corporation of Indiana 'Filed Apr. 17, 1961, tier. No. 103,312 4 Claims. (Cl. 29-156.8)

This invention relates to a method of assembling blower wheels or the like to dispose the set screws thereof in positions of access.

In the assembly of blower wheels of the type comprising a first end plate having a hub and interconnected to a second end plate by a fan blade strip, it has heretofore been the practice to completely assemble the blower wheel and then insert the set screw in the hub. This practice has been extremely time consuming, thus resulting in low production rates and high unit labor costs. More iniportantly, it has resulted in a substantial percentage of wheels having their SClW-I'fiCelVil'l hub openings disposed on the same radius as one of their fan blades, thus making it extremely difficult to insert and tighten the set screws in said openings.

It is thus the general object of my invention to provide a method which will overcome the dir'iiculties just discussed. More particularly, it is an object of my invention to provide an apparatus and method for making blower wheels or the like which will dispose the set screw openings therein in the desired locations, and which will permit the quick and economical assembly thereof.

According to one form of my invention a blower wheel end plate having a hub mounted thereon is disposed on a worktable having means for guiding sliding movements of the end plate thereon. Said end plate is movable on said worktable with respect to a rotatable tool carried on a supporting structure, said tool releasably carrying a set screw rotatable therewith for insertion in a tapped opening in said hub upon movement of the end plate into a position to dispose said screw in engagement with said opening. The tool has a greater length than the end plate radius and is retained in alignment with the inserted screw axis while a split fan strip is mounted on said end plate and secured in a fixed position thereon with its ends abutting the opposed sides of said tool to thus insure that the axis of said screw is disposed in alignment with the spacing between a pair of adjacent blades on said fan strip.

Other objects and features of my invention will become apparent from the more detailed description which follows and from the accompanying drawings, in which:

FIG. 1 is an isometric view of an apparatus embodying my invention, and showing a partially assembled blower wheel disposed thereon;

FIG. 2 is a vertical section taken on the longitudinal axis of the apparatus shown in FIG. 1, but showing the blower wheel in assembled position and the hub locator removed therefrom;

FIG. 3 is a top plan view of the apparatus shown in FIG. 1, but with portions thereof broken away;

FIG. 4 is a fragmentary vertical section taken on the line 4-4 of FIG. 3;

FIG. 5 is a fragmentary vertical section taken on the line 55 of FIG. 3;

FIG. 6 is a fragmentary vertical section taken on the line 66 of FIG. 3;

FIG. 7 is an enlarged fragmentary isometric view of the end plate and hub locator shown in FIG. 1; and

FIG. 8 is an enlarged isometric view of a modified form of the end plate and hub locator shown in FIG. 7.

This invention is concerned with an apparatus and method for locating and starting set screws, particularly set screws in blower wheels. As shown in PEG. 2, a

3,153,842 Patented Qct. 27, 1964 conventional blower wheel may comprise a pair of end plates iii and 12 provided with opposed circumferentially extending channels 14. The end plate 10 is provided with an opening on its axis in which an axially projecting hub 15 is fixedly mounted. In many such wheels, the hub is mounted on the end plate 19 by an annular flange 16 rigidly secured to said end plate and projecting outwardly therefrom. The end plates 14! and 12 are interconnected by a split fan strip having a plurality of circumferentially spaced blades 18, with the opposed edges of the strip 18 being received in the plate channels 14 and the legs of said channels being spun against the strip to rigidly lock the end plates thereon and hold thewheel assembled. Such a wheel is mounted on its driver shaft by a set screw 2%) received in a tapped opening'formed in the cylindrical wall of the hub 15. In order that the set screw 29 may be tightened or loosened, it is necessary that said screw be-radially aligned with the spacing between a pair of the adjacent fan blades 18. This invention is concerned with an apparatus and method for assembling blower wheels to dispose their set screws in such alignment with the radial spacing between an adjacent pair of the blades 13.

The illustrated embodiment of my invention comprises a supporting structure formed from an upright wall 23 and 'leg24- interconnected by a plurality of frame members 25. A'motor 26 is mounted on one of the frame members 25 and has its drive shaft 27 connected to an arbor 28. As shown in FIG. 2, the arbor 28, which is rotatable with the drive shaft 27, is journaled in a fixed position in openings formed in the frame members 25 and the wall 23 and projects outwardly from said wall 23. A mounting plate 3i extends across the face of the wall 23 remote from the motor 26 and supports a worktable 32 connected to the plate 319 by bolts 33 and by a pair of braces 34 connected to the worktable 32 by bolts 35 and to the plate 34) by bolts 36. The worktable 32 and plate 3% are adjustably mounted on the wall 23 by bolts 38 which extend through a pair of vertically extending adjusting slots 44 formed in the wall 23 for reception in said worktable and supporting plate. Thus, upon loosening of the bolts 38, the worktable 32 may be vertically adjusted with respect to the axis of the arbor 28 extending through the wall 23 and projecting over said worktable.

The worktable 32 is adapted to support the blower wheel end plate 11?, and to this end, it is provided with a longitudinally extending channel 42 in which the hub flange 16 is received when the end plate is placed upon the upwardly presented face of the worktable. Conveniently, the worktable 32 is provided with pairs of longitudinally spaced, transverse slots 44 for the reception of bolts 46 extending through a pair of guide bars 43. As shown in FIG. 1, the guide bars 43 are laterally adjustable to engage diametrically opposed edges of an end plate 19 to thus guide said end plate as it is slid over the face of the worktable toward and away from the arbor 23.

in order to align the axis of the tapped screw-receiving opening in the hub 15 with the axis of the arbor 23, I provide locator means for angularly orienting said hub about its axis. Two embodiments of such locator means are illustrated in FIGS. 7 and 8. The embodiment shown in FIG. 7 comprises a block 50 slidable in the channel 42 and provided with a pair of outwardly projecting, L-shaped fingers 52 receivable in opposed recesses 54 milled in the outer side walls of the hub 15. Each of the recesses 54 is located from the axis of the tapped hub opening and parallel thereto, and thus with the fingers 52 received in said recesses the hub will be releasably retained in position to dispose the axis of its tapped opening in alignment with the axes of the arbor 28 and screw 2% when the worlrtable 32 is disposed in the proper position of vertical adjustment with respect to said arbor.

An alternative locator construction is shown in FIG. 8, and comprises a block 5% slidable in the worktable channel 42 and provided with an upwardly projecting button 55 receivable in a dimple formed in the end plate adjacent its circumference and oriented 180 from the tapped opening in the hub 15. As will be apparent,

the locator constructions shown in both FIGS. 7 and 8 are slidable in the worktable channel 42 to thus retain the end plate hub in the proper orientation with respect to the axis of the arbor 28 as the end plate is moved toward said arbor. Since the locators shown in FIGS. 7 and 8 releasably retain the end plate in a fixed position about its own axis and in a fixed orientation with respect to the axis of the arbor 28, they may be used either in combination wtih the guide bars 43 or as alternatives thereof for guiding the sliding movements of the end plate 10.

In order that the arbor 28 will start the set screw into the tapped opening in the hub 15 upon movement of the end plate into a position in which said screw en- ,gages said opening and to accurately control the depth to which said screw is inserted into the opening, I conveniently provide switch means for controlling the starting and stopping of the arbor driving motor 26 relative to the movement of the end plate 15 toward said arbor. As shown in FIGS. 2 and 5, such a control assembly comprises a block 58 mounted on the underside of the worktable 32 by bolts 59 received in longitudinally extending openings 6%) formed in said worktable. A pair of support members 62 are fixedly mounted on the opposite sides of the block 58, with one of said support members carrying a forwardly disposed motor-starting switch 64 and the other of said supporting members carrying a rearwardly disposed motor-stopping switch 65. As shown in FIG. 3, each of the switches 64 and 65 projects upwardly from its supporting member 62 through longitudinally extending slots 66 formed in the worktable 32 to dispose their actuating ends slightly above the upwardly presented face of the worktable for engagement with the end plate 16 as said end plate is moved toward the arbor 28(The switches 64 and 65 are connected to the arbor motor 26 so that as the end plate 10 is moved toward the arbor 28, the switch 64 will energize the motor 26 to rotate the arbor when the tapped hub opening is disposed in engagement with the set screw 2%. The arbor will continue to rotate to insert the screw 20 in the hub opening until the end plate 10 has been advanced to a position to engage the motor-stopping switch 65, which will de-energize the motor 26 and thus prevent the set screw from being inserted to too great a depth in the hub opening. The longitudinally extending openings 60 and 66 permit the block 58 to be movable longitudinally of the arbor 28 for thus adjusting the positions of the switches 64 and 65 relative to said arbor. In this manner, my switching assembly may thus be adapted for use on end plates having different radii.

An alternative of the switch control for controlling the depth to which the screw is inserted is shown in FIGS. 3 and 5, and comprises a pair of pins 69 mounted on the worktable 32 outwardly from the wall 23 for engagement with the end plate as it is moved toward said wall. In this modification, the arbor motor 26 is operated manually, and the depth to which the screw 20 may be inserted in the hub opening is controlled by positioning of the pins 69 relative to the wall 23.

In the. operation of my apparatus, an end plate 10 having a hub 15 mounted thereon is disposed on the worktable 32, and said worktable is adjusted by means of the screws 33 to position the tapped screw-receiving opening in said hub in horizontal alignment with the arbor 28. The guide bars are-then brought into contact with the end plate 10 to position the hub opening in vertical alignment with the arbor axis, and to retain said alignment as the end plate is slid toward the arbor. A locator, such as shown in FIGS. 7 and 8, is disposed in operative engagement with the end plate-hub assembly to orient the hub about its axis to dispose its tapped opening in precise alignment with the axis of the screw 20 and arbor 23. The end plate is then advanced toward the wall 23 and arbor 28, and the screw 20 is rotatably threaded into the hub opening to a predetermined depth, as by the operation of the switches 64 and 65 previously described.

The sequence of operations just described will locate and start a set screw into various hub and end plate assemblies. Where such hub constitutes a component of a blower wheel of the type shown in the drawings, the end plate is maintained in the position illustrated in FIG. 2 after the set screw 2i? has been inserted in the hub to the desired depth. With the arbor 28 remaining in alignment with the axis of the screw 20 and projecting outwardly from said hub, the split fan strip containing the blades 15 is then placed in the channel 14 of the end plate 15) with the ends of said strip disposed on opposite sides of the arbor 28. In this manner, the arbor will be interposed between a pair of the adjacent blades 18. Of course, when the locator shown in FIG. 7 is employed, said locator is removed from the hub 15 prior to placement of the fan strip on the end plate so that the locator fingers 52 do not interfere with the proper positioning of said fan strip. The end plate 12 is then placed on the fan strip with its channel 14 being received over the edge of said strip opposite the plate 10. The inherent resiliency of the split fan strip causes said fan strip to bear against the walls of the channels 14 on the pair of end plates to thus retain said fan strip in position therein while the wheel assembly is withdrawn from the arbor 28. The legs of the channels 14 on the the end plates 14) and 12 are then rigidly fastened to the fan strip, such as by staking, spinning against sm'd fan strip, or the like, to rigidly retain said fan strip in a fixed orientation about the axis of the wheel and interconnect the several wheel components. With the wheel being assembled while the arbor 28 is in operative engagement therewith between a pair of adjacent blades 18, alignment between the set screw 29 and the spacing between a pair of adjacent blades 18 will be assured so that a tool may be inserted between said blades for tightening said set screw when the wheel is subsequently placed in operative position on a driving member re ceived in the hub 15.

I claim:

1. A method for locating and starting a set screw in a blower wheel of the type comprising a first end plate having a hub and connected to a second end plate by a split annular fan strip having a series of spaced blades, comprising the steps of supporting in a fixed radial position with respect to said hub a tool having a set screw releasably carried thereon, moving said first end plate with respect to said tool to dispose said hub in engagement with said screw and rotating said tool to start said screw into a tapped opening formed in said hub, retaining said tool in alignment with the axes of said screw and opening and projecting radially outwardly from said hub beyond the extent of said first end plate, placing said split fan strip on said first end plate in a circumscribing position around said hub with the ends of said strip disposed on opposite sides of said tool, placing said second end plate on said strip to retain the same in a fixed angular position about the axis of said hub, and withdrawing the wheel from said tool.

2. A method for locating and starting a set screw in a blower wheel of the type comprising a first end plate having a hub and connected to a second end plate by a split annular fan strip having a series of spaced blades, comprising the steps of supporting in a fixed radial position with respect to said hub a tool having a set screw releasably carried thereon, moving said first end plate toward said screw to dispose said hub in contact therewith, rotating said tool upon engagement of said screw and hub and continuing said movement of said end plate whereby said tool will threadably insert said screw in a tapped opening in said hub, said continuing movement and rotation being stopped substantially concurrently whereby said screw Will be inserted in said opening to a controlled depth, retaining said tool in alignment with the axes of said screw and opening and projecting radially outwardly from said hub beyond the extent of said first end plate, placing said split {an strip on said first end plate in a circumscribing position around said hub with the ends of said strip disposed on opposite sides of said tool, placing said second end plate on said strip to retain the same in a fixed angular position about the axis of said hub, and withdrawing the wheel from said tool.

3. A method for locating and starting a set screw in a blower wheel of the type comprising a first end plate having a hub and connected to a second end plate by a split annular fan strip having a series of spaced blades, comprising the steps of placing said first end plate and hub on a worktable in a fixed orientation, releasably loclting said first end plate and hub in said orientation, sliding said end plate on said worktable toward a fixedly mounted rotatable tool having a set screw carried thereon to bring said screw in operative contact with a tapped opening formed in said hub, rotating said tool while said sliding movement is continued to insert said screw in said opening, substantially concurrently stopping said rotation and sliding movement, retaining said tool in alignment with the axes of said screw and opening and projecting radially outwardly from said hub beyond the extent of said first end plate, placing said split fan strip on said first end plate in a circumscribing position around said hub with the ends of said strip disposed on opposite sides of said tool, placing said second end plate on said strip to retain the same in a fixed angular position about the axis of said hub, unlocking said first end plate and hub from said fixed orientation, and withdrawing the wheel from said tool.

4. The method as set forth in claim 3 in which said step of unlocking said first end plate and hub from their fixed orientation is carried out prior to the step of placing said fan strip on said first end plate.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A METHOD FOR LOCATING AND STARTING A SET SCREW IN A BLOWER WHEEL OF THE TYPE COMPRISING A FIRST END PLATE HAVING A HUB AND CONNECTED TO A SECOND END PLATE BY A SPLIT ANNULAR FAN STRIP HAVING A SERIES OF SPACED BLADES, COMPRISING THE STEPS OF SUPPORTING A FIXED RADIAL POSITION WITH RESPECT TO SAID HUB A TOOL HAVING A SET SCREW RELEASABLY CARRIED THEREON, MOVING SAID FIRST END PLATE WITH RESPECT TO SAID TOOL TO DISPOSE SAID HUB IN ENGAGEMENT WITH SAID SCREW AND ROTATING SAID TOOL TO START SAID SCREW INTO A TAPPED OPENING FORMED IN SAID HUB, RETAINING SAID TOOL IN ALIGNMENT WITH AXES OF SAID SCREW AND OPENING AND PROJECTING RADIALLY OUTWARDLY FROM SAID HUB BEYOND THE EXTENT OF SAID FIRST END PLATE, PLACING SAID SPLIT FAN STRIP ON SAID FIRST END PLATE, IN A CIRUMSCRIBING POSITION AROUND SAID HUB WITH THE ENDS OF SAID STRIP DISPOSED ON OPPOSITE SIDES OF SAID TOOL, PLACING SAID SECOND END PLATE ON SAID STRIP TO RETAIN THE SAME IN A FIXED ANGULAR POSITION ABOUT THE AXIS OF SAID HUB, AND WITHDRAWING THE WHEEL FROM SAID TOOL. 